2119981 has 4 divisors (see below), whose sum is σ = 2122912. Its totient is φ = 2117052.

The previous prime is 2119969. The next prime is 2120009. The reversal of 2119981 is 1899112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2119981 - 2¹³ = 2111789 is a prime.

It is a super-2 number, since 2×2119981² = 8988638880722, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2119921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 490 + ... + 2116.

It is an arithmetic number, because the mean of its divisors is an integer number (530728).

2^2119981 is an apocalyptic number.

It is an amenable number.

2119981 is a deficient number, since it is larger than the sum of its proper divisors (2931).

2119981 is a wasteful number, since it uses less digits than its factorization.

2119981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2930.

The product of its digits is 1296, while the sum is 31.

The square root of 2119981 is about 1456.0154532147. The cubic root of 2119981 is about 128.4627819965.

It can be divided in two parts, 21 and 19981, that added together give a palindrome (20002).

The spelling of 2119981 in words is "two million, one hundred nineteen thousand, nine hundred eighty-one".